Tarek El Moussa has built a million-dollar real-estate empire thanks to HGTV. He said it took hitting rock bottom to get to where he is today.

• Tarek El Moussa's book, "Flip Your Life," was released Tuesday. 
• The star opened up about his past — including his addiction and divorce — in the book.
• He told Business Insider that the low points in his life helped him grow.

It's 6:30 a.m., and Tarek El Moussa has been awake for hours.

As an HGTV star, home flipper, real-estate investor, husband, and father of three, El Moussa's days are packed, to put it mildly. El Moussa, 42, works so much that he told Business Insider he doesn't have time to think about what he wants to accomplish unless he wakes up by 4 a.m.